{"id":19631,"date":"2018-12-13T09:00:14","date_gmt":"2018-12-13T00:00:14","guid":{"rendered":"http:\/\/www.techscore.com\/blog\/?p=19631"},"modified":"2018-12-13T17:48:34","modified_gmt":"2018-12-13T08:48:34","slug":"java-process-thread-study","status":"publish","type":"post","link":"https:\/\/www.techscore.com\/blog\/2018\/12\/13\/java-process-thread-study\/","title":{"rendered":"Java\u3067\u306e\u30d7\u30ed\u30bb\u30b9\u30fb\u30b9\u30ec\u30c3\u30c9\u306b\u3064\u3044\u3066\u52c9\u5f37\u3057\u305f\u307e\u3068\u3081"},"content":{"rendered":"<p>\u3053\u3093\u306b\u3061\u306f\u3002\u938c\u7530\u3067\u3059\u3002<br \/>\n\u3053\u308c\u306f <a href=\"\/blog\/2018\/11\/22\/techscore-advent-calendar-2018\/\">TECHSCORE Advent Calendar 2018<\/a>\u306e13\u65e5\u76ee\u306e\u8a18\u4e8b\u3067\u3059\u3002<\/p>\n<p>Java \u3067\u306e\u30d7\u30ed\u30bb\u30b9\u3084\u30b9\u30ec\u30c3\u30c9\u306e\u5b9f\u88c5\u65b9\u6cd5\u3064\u3044\u3066\u3042\u307e\u308a\u7406\u89e3\u3067\u304d\u3066\u3044\u308b\u6c17\u304c\u305b\u305a\u3001\u3042\u3089\u305f\u3081\u3066\u52c9\u5f37\u3059\u308b\u610f\u5473\u3067\u89e6\u3063\u305f\u3053\u3068\u3092\u8a18\u4e8b\u306b\u3057\u307e\u3057\u305f\u3002\u672c\u8a18\u4e8b\u3067\u89e6\u308c\u3066\u3044\u308b\u30b9\u30ec\u30c3\u30c9\u3084\u30de\u30eb\u30c1\u30b9\u30ec\u30c3\u30c9\u306b\u3064\u3044\u3066\u306f\u3001<a href=\"http:\/\/www.techscore.com\/tech\/Java\/JavaSE\/Thread\/index\/\">TECHSCORE\u672c\u5bb6\u30b5\u30a4\u30c8<\/a>\u3067\u3082\u8a73\u3057\u304f\u8aac\u660e\u304c\u3055\u308c\u3066\u3044\u308b\u306e\u3067\u305c\u3072\u3054\u53c2\u7167\u304f\u3060\u3055\u3044\uff01<\/p>\n<p>\u4eca\u56de\u306e\u8a18\u4e8b\u3067\u4f7f\u7528\u3057\u305f\u30d0\u30fc\u30b8\u30e7\u30f3\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<br \/>\n<a href=\"https:\/\/www.oracle.com\/technetwork\/java\/javase\/downloads\/jre8-downloads-2133155.html\">Java:1.8.0<\/a><\/p>\n<h2>\u76ee\u6b21<\/h2>\n<ul>\n<li><a href=\"#Process\">\u30d7\u30ed\u30bb\u30b9<\/a><\/li>\n<li><a href=\"#Thread\">\u30b9\u30ec\u30c3\u30c9<\/a><\/li>\n<li><a href=\"#synchronized\">\u6392\u4ed6\u5236\u5fa1(synchronized)<\/a><\/li>\n<li><a href=\"#semaphore\">\u540c\u6642\u5b9f\u884c\u6570\u5236\u5fa1<\/a><\/li>\n<li><a href=\"#threadpool\">\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb<\/a><\/li>\n<li><a href=\"#fin\">\u304a\u308f\u308a\u306b<\/a><\/li>\n<\/ul>\n<h2 id=\"Process\">\u30d7\u30ed\u30bb\u30b9<\/h2>\n<p>\u30d7\u30ed\u30bb\u30b9\u3092\u751f\u6210\u3059\u308b\u5834\u5408\u306f<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/lang\/ProcessBuilder.html\">java.lang.ProcessBuilder<\/a>\u3092\u4f7f\u3044\u307e\u3059\u3002<br \/>\nstart() \u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u3067\u30d7\u30ed\u30bb\u30b9\u3092\u8d77\u52d5\u3057\u307e\u3059\u3002\u6a19\u6e96\u51fa\u529b\u304c\u3042\u308b\u30b3\u30de\u30f3\u30c9\u306f\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u306e\u3088\u3046\u306b\u3001<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/io\/InputStream.html\">java.io.InputStream<\/a>\u3092\u4f7f\u3046\u3053\u3068\u3067\u7d50\u679c\u3092\u53d6\u5f97\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:java decode:true mark:7,8\" title=\"ProcessTest.java\" >import java.io.IOException;\nimport java.io.InputStream;\n\npublic class ProcessTest {\n    public static void main(String args[]) {\n        try {\n            ProcessBuilder builder = new ProcessBuilder(\"ps\");\n            Process process = builder.start();\n            InputStream is = process.getInputStream();\n            while (true) {\n                int c = is.read();\n                if (c == -1) {\n                    is.close();\n                    break;\n                }\n                System.out.print((char) c);\n            }\n        } catch (IOException e) {\n            e.printStackTrace();\n        }\n    }\n}\n<\/pre>\n<p>\u30b3\u30f3\u30d1\u30a4\u30eb\u3057\u3066\u5b9f\u884c\u3059\u308b\u3068\u3061\u3083\u3093\u3068\u300c<strong>ps<\/strong>\u300d\u30b3\u30de\u30f3\u30c9\u306e\u7d50\u679c\u304c\u8868\u793a\u3055\u308c\u307e\u3057\u305f\uff01<\/p>\n<pre>\n$ javac ProcessTest.java\n$ java ProcessTest\n   PID TTY          TIME CMD\n 13223 pts\/4    00:00:00 java\n 13238 pts\/4    00:00:00 ps\n<\/pre>\n<p>Linux \u4e0a\u3067\u306f\u3069\u306e\u3088\u3046\u306b\u898b\u3048\u308b\u306e\u3067\u3057\u3087\u3046\u304b\u3002\u30b3\u30de\u30f3\u30c9\u3092\u300cps\u300d\u304b\u3089\u300c<strong>sleep 100<\/strong>\u300d\u306b\u5909\u3048\u3066\u3001\u30d7\u30ed\u30bb\u30b9\u306e\u72b6\u614b\u3092\u307f\u307e\u3059\u3002\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u5b9f\u884c\u4e2d\u306b\u30d7\u30ed\u30bb\u30b9\u3092\u78ba\u8a8d\u3059\u308b\u3068\u3001\u5b50\u30d7\u30ed\u30bb\u30b9\u3068\u3057\u3066\u30b3\u30de\u30f3\u30c9\u304c\u5b9f\u884c\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u304c\u5206\u304b\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"lang:Shell mark:6 decode:true \" >\n$ java ProcessTest &\n[1] 13346\n$ ps f --ppid $! --pid $!\n   PID TTY      STAT   TIME COMMAND\n 13346 pts\/4    Sl+    0:00 java ProcessTest\n 13361 pts\/4    S+     0:00  \\_ sleep 100\n<\/pre>\n<h2 id=\"Thread\">\u30b9\u30ec\u30c3\u30c9<\/h2>\n<p>\u30b9\u30ec\u30c3\u30c9\u3092\u4f7f\u3046\u3053\u3068\u3067\u975e\u540c\u671f\u306a\u51e6\u7406\u3092\u3055\u305b\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u30b9\u30ec\u30c3\u30c9\u3092\u751f\u6210\u3059\u308b\u306b\u306f <a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/lang\/Thread.html\">java.lang.Thread<\/a>\u3092\u7d99\u627f\u3057\u305f\u30af\u30e9\u30b9\u3092\u4f5c\u6210\u3057\u3066 start() \u3092\u547c\u3073\u51fa\u3059\u3053\u3068\u3067\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:java decode:true mark:16,17\" title=\"ThreadTest.java\" >\npublic class ThreadTest {\n    static class SampleThread1 extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < 26; i++) {\n                System.out.print(i);\n                try {\n                    sleep(1000);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        }\n    }\n    public static void main(String args[]) {\n        Thread thread1 = new SampleThread1();\n        thread1.start();\n        String[] Alphabet = { \"a\", \"b\", \"c\", \"d\", \"e\", \"f\", \"g\", \"h\", \"i\", \"j\", \"k\", \"l\", \"m\", \"n\", \"o\", \"p\", \"q\",\n                \"r\", \"s\", \"t\", \"u\", \"v\", \"w\", \"x\", \"y\", \"z\" };\n        for (int i = 0; i < 26; i++) {\n            System.out.print(Alphabet[i]);\n                try {\n                    Thread.sleep(1500);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n        }\n    }\n}\n<\/pre>\n<p>\u5b9f\u884c\u7d50\u679c\u3092\u307f\u308b\u3068\u6570\u5b57\u3068\u30a2\u30eb\u30d5\u30a1\u30d9\u30c3\u30c8\u304c\u4ea4\u4e92\u306b\u51fa\u529b\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u30b9\u30ec\u30c3\u30c9\u306b\u5206\u3051\u305a\u306b\u5b9f\u884c\u3059\u308b\u30681-25\u307e\u3067\u306e\u6570\u5b57\u306e\u3042\u3068\u306ba-z\u307e\u3067\u306e\u30a2\u30eb\u30d5\u30a1\u30d9\u30c3\u30c8\u304c\u51fa\u529b\u3055\u308c\u308b\u306e\u3067\u3001\u975e\u540c\u671f\u306b\u51e6\u7406\u304c\u3055\u308c\u3066\u305d\u3046\u3067\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:zsh decode:true\" >\n$ java ThreadTest\n a0b1c23de4f5g6h7i89j10kl1112m13no1415p16qr17s18t19u20v21w22x2324y25z\n<\/pre>\n<p>\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3092\u5b9f\u884c\u3057\u3066<a href=\"https:\/\/docs.oracle.com\/javase\/8\/docs\/technotes\/tools\/unix\/jstack.html\">jstack<\/a>\u3067\u78ba\u8a8d\u3059\u308b\u3068\u30e1\u30a4\u30f3\u30b9\u30ec\u30c3\u30c9\u3068\u306f\u5225\u306b\u30b9\u30ec\u30c3\u30c9\u304c\u751f\u6210\u3055\u308c\u3066\u51e6\u7406\u3057\u3066\u3044\u308b\u3053\u3068\u304c\u5206\u304b\u308a\u307e\u3059\u3002<br \/>\n<a href=\"https:\/\/docs.oracle.com\/javase\/8\/docs\/technotes\/tools\/unix\/jstack.html\">jstack<\/a>\u306fjava\u30d7\u30ed\u30bb\u30b9\u306e\u30b9\u30ec\u30c3\u30c9\u306e\u72b6\u614b\u3092\u78ba\u8a8d\u3067\u304d\u308b\u30b3\u30de\u30f3\u30c9\u3067\u3001<strong>\u30b9\u30ec\u30c3\u30c9\u540d<\/strong>(Thread-0),<strong>\u512a\u5148\u5ea6<\/strong>(prio),<strong>\u30b9\u30ec\u30c3\u30c9\u306e\u72b6\u614b<\/strong>(java.lang.Thread.State),<strong>jvm\u4e0a\u306e\u30b9\u30ec\u30c3\u30c9ID<\/strong>(tid),<strong>OS\u4e0a\u306e\u30b9\u30ec\u30c3\u30c9ID<\/strong>(nid)\u3084\u3001\u3069\u306e\u30e1\u30bd\u30c3\u30c9\u3092\u51e6\u7406\u4e2d\u304b\u306a\u3069\u3092\u8868\u793a\u3057\u3066\u304f\u308c\u308b\u306e\u3067\u8abf\u67fb\u306a\u3069\u3067\u975e\u5e38\u306b\u6709\u7528\u3067\u3059\u3002<\/p>\n<pre>\n$ java ThreadTest &\n[1] 14587\n$ jstack 14587 \n...\n# \u751f\u6210\u3055\u308c\u305f\u30b5\u30d6\u30b9\u30ec\u30c3\u30c9\n\"Thread-0\" #9 prio=5 os_prio=0 tid=0x00007f7a340ea330 nid=0x3aad waiting on condition [0x00007f7a215e6000] \n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadTest$SampleThread1.run(ThreadTest.java:9)\n\n...\n# \u30e1\u30a4\u30f3\u30b9\u30ec\u30c3\u30c9\n\"main\" #1 prio=5 os_prio=0 tid=0x00007f7a34009340 nid=0x3a9d waiting on condition [0x00007f7a3c387000] \n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadTest.main(ThreadTest.java:26)\n...\n<\/pre>\n<h2 id=\"synchronized\">\u6392\u4ed6\u5236\u5fa1(synchronized)<\/h2>\n<p>\u6392\u4ed6\u5236\u5fa1\u306e\u3084\u308a\u65b9\u306f\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\u304c\u3001\u4eca\u56de\u306f<strong>synchronized<\/strong>\u3092\u4f7f\u3044\u307e\u3059\u3002<strong>synchronized<\/strong>\u3092\u4f7f\u3046\u3053\u3068\u30671\u3064\u306e\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306b\u5bfe\u3057\u3066\u3001\u8907\u6570\u306e\u30b9\u30ec\u30c3\u30c9\u304c\u540c\u6642\u306b\u51e6\u7406\u3092\u884c\u308f\u306a\u3044\u3088\u3046\u306b\u5236\u5fa1\u3067\u304d\u307e\u3059\u3002<strong>synchronized<\/strong>\u3059\u308b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u306f<a href=\"http:\/\/www.jpcert.or.jp\/java-rules\/lck01-j.html\">\u6ce8\u610f<\/a>\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:java decode:true mark:2,7\" title=\"ThreadTest.java\" >\npublic class ThreadTest {\n    private static final Object lock = new Object(); \/\/ synchronized\u306e\u305f\u3081\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\n\n    static class SampleThread1 extends Thread {\n        @Override\n        public void run() {\n            synchronized (lock) { \/\/ lock \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3057\u3066\u540c\u671f\u3092\u53d6\u308b\n                for (int i = 0; i < 10; i++) {\n                    System.out.print(i + \" \");\n                    try {\n                        sleep(1000);\n                    } catch (InterruptedException e) {\n                        e.printStackTrace();\n                    }\n                }\n            }\n        }\n    }\n\n    public static void main(String args[]) {\n        Thread thread1 = new SampleThread1();\n        Thread thread2 = new SampleThread1();\n        thread1.start();\n        thread2.start();\n    }\n}\n<\/pre>\n<p>\u7d50\u679c\u306e\u6bd4\u8f03\u3092\u7528\u610f\u3057\u305f\u306e\u3067\u5206\u304b\u308a\u3084\u3059\u3044\u3068\u601d\u3044\u307e\u3059\u3002<a href=\"#Thread\">\u30b9\u30ec\u30c3\u30c9<\/a>\u306e\u3068\u304d\u306e\u5b9f\u884c\u7d50\u679c\u3068\u306f\u9055\u3044\u3001\u9806\u756a\u3069\u304a\u308a\u306b\u6570\u5b57\u304c\u51fa\u529b\u3055\u308c\u3066\u304a\u308a lock \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u6301\u3063\u3066\u3044\u308b\u30b9\u30ec\u30c3\u30c9\u306e\u307f\u304c\u51e6\u7406\u3092\u3057\u3066\u304a\u308a\u3001\u6301\u3063\u3066\u3044\u306a\u3044\u30b9\u30ec\u30c3\u30c9\u306f\u5f85\u3061\u72b6\u614b\u3067\u3059\u3002<\/p>\n<pre>\n$ java ThreadTest #\u6392\u4ed6\u5236\u5fa1\u3057\u3066\u3044\u308b\n0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9\n$ java ThreadTest #\u6392\u4ed6\u5236\u5fa1\u3057\u3066\u3044\u306a\u3044\n0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 \n<\/pre>\n<p>jstack \u3082\u53d6\u308a\u307e\u3057\u305f\u3002Thread-0 \u306f sleep() \u3092\u5b9f\u884c\u4e2d\u306711\u884c\u76ee\u306b\u300c<strong>- locked <0x00000000ec4622f8> (a java.lang.Object)<\/strong>\u300d\u3068\u8868\u793a\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u3053\u308c\u306f\u30bd\u30fc\u30b9\u30b3\u30fc\u30c9\u4e2d\u306e lock \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u30ed\u30c3\u30af\u3092\u53d6\u5f97\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u793a\u3057\u3066\u3044\u307e\u3059\u3002<br \/>\nThread-1 \u306f\u72b6\u614b\u304c<strong>BLOCKED<\/strong>\u306b\u306a\u3063\u3066\u304a\u308a\u51e6\u7406\u3092\u30d6\u30ed\u30c3\u30af\u3055\u308c\u3066\u3044\u308b\u3088\u3046\u3067\u3059\u30025\u884c\u76ee\u3067\u300c<strong> - waiting to lock <0x00000000ec4622f8> (a java.lang.Object)<\/strong>\u300d\u3068\u8868\u793a\u3055\u308c\u3066\u3044\u308b\u306e\u3067 Thread-0 \u304c\u30ed\u30c3\u30af\u3092\u3057\u3066\u3044\u308b lock \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u30ed\u30c3\u30af\u5f85\u3061\u3092\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u793a\u3057\u3066\u3044\u307e\u3059\u3002<br \/>\n(\u30b9\u30ec\u30c3\u30c9\u306e\u72b6\u614b\u306f<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/lang\/Thread.State.html\">JavaDoc<\/a>\u306b\u8aac\u660e\u304c\u8a18\u8f09\u3055\u308c\u3066\u3044\u307e\u3059)<\/p>\n<pre class=\"lang:Shell mark:6,12 decode:true \" >\n...\n#\u30ed\u30c3\u30af\u5f85\u3061\u3057\u3066\u3044\u308b\u30b9\u30ec\u30c3\u30c9\n\"Thread-1\" #11 prio=5 os_prio=0 tid=0x00007f55f40fb590 nid=0x4404 waiting for monitor entry [0x00007f55cfaf9000]\n   java.lang.Thread.State: BLOCKED (on object monitor)\n        at ThreadTest$SampleThread1.run(ThreadTest.java:8)\n        - waiting to lock <0x00000000ec4622f8> (a java.lang.Object)\n#\u5148\u306b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u30ed\u30c3\u30af\u3092\u53d6\u5f97\u3057\u305f\u30b9\u30ec\u30c3\u30c9\n\"Thread-0\" #10 prio=5 os_prio=0 tid=0x00007f55f40fa520 nid=0x4403 waiting on condition [0x00007f55cfbfa000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadTest$SampleThread1.run(ThreadTest.java:11)\n        - locked <0x00000000ec4622f8> (a java.lang.Object)\n...\n<\/pre>\n<h2 id=\"semaphore\">\u5b9f\u884c\u6570\u5236\u5fa1<\/h2>\n<p>\u30b9\u30ec\u30c3\u30c9\u306e\u540c\u6642\u5b9f\u884c\u6570\u306e\u5236\u5fa1\u3067\u3059\u3002<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/util\/concurrent\/Semaphore.html\">java.util.concurrent.Semaphore<\/a>\u3092\u4f7f\u3044\u307e\u3059\u3002<strong>Semaphore<\/strong>\u3082\u6392\u4ed6\u5236\u5fa1\u306e1\u3064\u3067\u3059\u3002\u5171\u6709\u8cc7\u6e90\u306b\u5bfe\u3057\u3066\u540c\u6642\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u308b\u6570\u3092\u793a\u3057\u3066\u3044\u307e\u3059\u3002\u4eca\u56de\u306e\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3067\u306f\u4f8b\u3068\u306a\u308b\u3088\u3046\u306a\u5171\u6709\u8cc7\u6e90\u306f\u7528\u610f\u305b\u305a\u3001<strong>Semaphore<\/strong>\u306e\u6a5f\u80fd\u3060\u3051\u3092\u8a66\u3057\u3066\u3044\u307e\u3059\u3002<br \/>\n<strong>Semaphore<\/strong>\u30925\u306b\u8a2d\u5b9a\u3057\u3066\u3001\u30b9\u30ec\u30c3\u30c9\u304c\u540c\u6642\u306b5\u3064\u307e\u3067\u51e6\u7406\u3067\u304d\u308b\u3088\u3046\u306a\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u3059\u300228\u884c\u76ee\u3067<strong>Semaphore<\/strong>\u3092\u8a2d\u5b9a\u3057\u3066\u30b9\u30ec\u30c3\u30c9\u3092\u751f\u6210\u3059\u308b\u3068\u304d\u306b<strong>Semaphore<\/strong>\u3092\u6e21\u3057\u3066\u3044\u307e\u3059\u3002<strong>Semaphore<\/strong>\u306f15\u884c\u76ee\u306eacquire() \u306b\u3088\u3063\u3066\u7372\u5f97\u3055\u308c1\u6e1b\u308a\u307e\u3059\u3002<strong>Semaphore<\/strong>\u304c0\u306b\u306a\u308b\u3068<strong>Semaphore<\/strong>\u3092\u7372\u5f97\u3067\u304d\u306a\u3044\u30b9\u30ec\u30c3\u30c9\u306f\u51e6\u7406\u304c\u59cb\u307e\u308a\u307e\u305b\u3093\u3002<br \/>\n22\u884c\u76ee\u306erelease()\u304c\u547c\u3073\u51fa\u3055\u308c\u305f\u6642\u70b9\u3067\u3001<strong>Semaphore<\/strong>\u304c\u89e3\u653e\u3055\u308c1\u5897\u3048\u307e\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:java decode:true mark:6,9,15,22,28,30\" title=\"SemaphoreTest.java\" >\nimport java.time.LocalTime;\nimport java.util.concurrent.Semaphore;\n\npublic class SemaphoreTest {\n    static class SampleThread1 extends Thread {\n        private Semaphore semaphore;\n\n        public SampleThread1(Semaphore semaphore) {\n            this.semaphore = semaphore;\n        }\n\n        @Override\n        public void run() {\n            try {\n                this.semaphore.acquire();\n                System.out.println(\"Thread:\" + Thread.currentThread().getId());\n                sleep(1000);\n            } catch (InterruptedException e) {\n                e.printStackTrace();\n            } finally {\n                System.out.println(LocalTime.now());\n                this.semaphore.release();\n            }\n        }\n    }\n\n    public static void main(String args[]) {\n        Semaphore semaphore = new Semaphore(5); \/\/Semaphore\u30925\u306b\u8a2d\u5b9a\u3057\u3066\u6e21\u3059\n        for (int i = 0; i <= 10; i++) {\n            Thread thread = new SampleThread1(semaphore);\n            thread.start();\n        }\n    }\n}\n<\/pre>\n<p>\u5b9f\u884c\u3059\u308b\u3068\u3061\u3083\u3093\u30685\u30b9\u30ec\u30c3\u30c9\u51e6\u7406\u3057\u305f\u3068\u3053\u308d\u3067<strong>Semaphore<\/strong>\u304c0\u306b\u306a\u308a\u3001\u65b0\u3057\u3044\u30b9\u30ec\u30c3\u30c9\u304c\u51e6\u7406\u3055\u308c\u306a\u304f\u306a\u308a\u307e\u3057\u305f\u3002<br \/>\n1\u79d2\u5f8c\u306b<strong>Semaphore<\/strong>\u304c\u89e3\u653e\u3055\u308c\u305f\u3053\u3068\u3067<strong>Semaphore<\/strong>\u306e\u7372\u5f97\u3092\u5f85\u3063\u3066\u3044\u305f\u30b9\u30ec\u30c3\u30c9\u304c\u51e6\u7406\u3092\u958b\u59cb\u3057\u307e\u3057\u305f\u3002<\/p>\n<pre>\nThread:10\nThread:11\nThread:12\nThread:14\nThread:13\u3000\/\/ 5\u30b9\u30ec\u30c3\u30c9\u5206\u306e\u51e6\u7406\u304c\u3055\u308cSemaphore \u304c0 \u306b\u306a\u308b\n08:29:02.034\n08:29:02.034\n08:29:02.034\n08:29:02.034\n08:29:02.034 \nThread:17 \/\/ Semaphore\u304c\u89e3\u653e\u3055\u308c\u308b\u307e\u3067\u5b9f\u884c\u3055\u308c\u306a\u3044\nThread:19\nThread:18\nThread:16\nThread:15\n08:29:03.035 \/\/ 1\u79d2\u5f8c\u306bSemaphore\u304c\u89e3\u653e\u3055\u308c\u3001\u6b21\u306e\u30b9\u30ec\u30c3\u30c9\u306e\u51e6\u7406\u304c\u5b9f\u884c\u3055\u308c\u308b\u3002\n08:29:03.035\nThread:20\n08:29:03.035\n...\n<\/pre>\n<p>jstack\u3067\u78ba\u8a8d\u3059\u308b\u3068\u5b9f\u884c\u5f85\u3061\u3092\u3057\u3066\u3044\u308b\u30b9\u30ec\u30c3\u30c9\u306e\u72b6\u614b\u304c<strong>WAITING<\/strong>\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002WAITING\u3068\u3044\u3046\u3053\u3068\u306f\u4ed6\u306e\u30b9\u30ec\u30c3\u30c9\u306e\u30a2\u30af\u30b7\u30e7\u30f3\u3092\u5f85\u3063\u3066\u3044\u307e\u3059\u3002\u300c<strong>- parking to wait for  <0x00000000ec4638f8> (a java.util.concurrent.Semaphore$NonfairSync)<\/strong>\u300d\u306e\u8868\u793a\u3068\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u306e acquire() \u306e\u51e6\u7406\u3067\u6b62\u307e\u3063\u3066\u3044\u308b\u3053\u3068\u304b\u3089<strong>Semaphore<\/strong>\u306e\u89e3\u653e\u3092\u5f85\u3063\u3066\u3044\u308b\u306e\u3060\u308d\u3046\u3068\u3044\u3046\u3053\u3068\u304c\u5206\u304b\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"lang:Shell mark:3,5,11 decode:true \" >\n...\n\"Thread-10\" #20 prio=5 os_prio=0 tid=0x00007efeb00ffb50 nid=0x1198 waiting on condition [0x00007efe8a8e7000]\n   java.lang.Thread.State: WAITING (parking)\n        at sun.misc.Unsafe.park(Native Method)\n        - parking to wait for  <0x00000000ec4638f8> (a java.util.concurrent.Semaphore$NonfairSync)\n        at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)\n        at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)\n        at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997)\n        at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304)\n        at java.util.concurrent.Semaphore.acquire(Semaphore.java:312)\n        at SemaphoreTest$SampleThread1.run(SemaphoreTest.java:15)\n...\n<\/pre>\n<p>\u3061\u306a\u307f\u306b\u3069\u306e\u30b9\u30ec\u30c3\u30c9\u304c<strong>Semaphore<\/strong>\u3092\u7372\u5f97\u3057\u3066\u3044\u308b\u304b\u30b9\u30ec\u30c3\u30c9\u30c0\u30f3\u30d7\u304b\u3089\u306f\u5206\u304b\u3089\u306a\u3044\u305d\u3046\u3067\u3059\u3002\u7406\u7531\u306f<strong>Semaphore<\/strong>\u306b\u306f\u6240\u6709\u3068\u3044\u3046\u6982\u5ff5\u304c\u306a\u3044\u305f\u3081\u3067\u3059\u3002\u305d\u306e\u305f\u3081<strong>Semaphore<\/strong>\u3092\u7372\u5f97\u3057\u305f\u30b9\u30ec\u30c3\u30c9\u3067\u306f\u306a\u304f\u3066\u3082<strong>Semaphore<\/strong>\u3092\u89e3\u653e\u3067\u304d\u308b\u3088\u3046\u3067\u3059\u3002<br \/>\n* \u53c2\u8003\uff1a<a href=\"http:\/\/d.hatena.ne.jp\/hsyd\/20120113\/1326480032\">[java]new Semaphore(0)<\/a><\/p>\n<h2 id=\"threadpool\">\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb<\/h2>\n<p>\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3068\u306f\u3042\u3089\u304b\u3058\u3081\u3044\u304f\u3064\u304b\u306e\u30b9\u30ec\u30c3\u30c9\u3092\u4f5c\u6210\u3057\u3066\u5f85\u6a5f\u3055\u305b\u3001\u30bf\u30b9\u30af\u304c\u6765\u305f\u3089\u3059\u3050\u306b\u30b9\u30ec\u30c3\u30c9\u3092\u5272\u308a\u5f53\u3066\u308b\u3053\u3068\u3067\u3001\u30b9\u30ec\u30c3\u30c9\u306e\u751f\u6210\u306e\u30b3\u30b9\u30c8\u3092\u6e1b\u3089\u305d\u3046\u3068\u3044\u3046\u3082\u306e\u3067\u3059\u3002<br \/>\nJava\u306e\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3082\u3044\u304f\u3064\u304b\u7a2e\u985e\u304c\u3042\u308a\u307e\u3059\u3002\u4eca\u56de\u306f\u6307\u5b9a\u3057\u305f\u6570\u306e\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3092\u751f\u6210\u3059\u308b <a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/util\/concurrent\/Executors.html#newFixedThreadPool-int-\">newFixedThreadPool<\/a>\u3092\u4f7f\u3044\u307e\u3059\u3002\u4ed6\u306b\u306f<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/util\/concurrent\/Executors.html#newCachedThreadPool--\">newCachedThreadPool<\/a>,<a href=\"https:\/\/docs.oracle.com\/javase\/jp\/8\/docs\/api\/java\/util\/concurrent\/Executors.html#newWorkStealingPool--\">newWorkStealingPool<\/a>\u304c\u3042\u308a\u307e\u3059\u3002<br \/>\n\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u306f100\u56de\u30b9\u30ec\u30c3\u30c9\u3092\u5b9f\u884c\u3059\u308b\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u3001\u51e6\u7406\u3057\u3066\u3044\u308b\u30b9\u30ec\u30c3\u30c9ID\u3092\u8868\u793a\u3059\u308b\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u3059\u3002<\/p>\n<pre class=\"toolbar:1 lang:java decode:true mark:18,20\" title=\"ThreadPoolTest.java\" >\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class ThreadPoolTest {\n    static class SampleThread1 extends Thread {\n        @Override\n        public void run() {\n            System.out.println(\"Thread:\" + Thread.currentThread().getId());\n            try {\n                sleep(1000);\n            } catch (InterruptedException e) {\n                e.printStackTrace();\n            }\n        }\n    }\n\n    public static void main(String args[]) {\n        ExecutorService fixedThreadPool = Executors.newFixedThreadPool(5);\u3000\/\/ \u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3092\u751f\u6210\n        for (int i = 0; i <= 100; i++)\u3000\/\/ 100\u500b\u306e\u30b9\u30ec\u30c3\u30c9\u3092\u5b9f\u884c\n            fixedThreadPool.execute(new SampleThread1());\n\n        fixedThreadPool.shutdown();\n    }\n}\n<\/pre>\n<p>\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3092\u4f7f\u308f\u306a\u3044\u30d7\u30ed\u30b0\u30e9\u30e0\u3082\u6bd4\u8f03\u3068\u3057\u3066\u5b9f\u884c\u3057\u307e\u3057\u305f\u3002<br \/>\n<strong>\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3042\u308a<\/strong>\u3067\u306f\u30b9\u30ec\u30c3\u30c9ID\u304c5\u7a2e\u985e\u3057\u304b\u8868\u793a\u3055\u308c\u306a\u3044\u306e\u3067\u30b9\u30ec\u30c3\u30c9\u3092\u4f7f\u3044\u307e\u308f\u3057\u3066\u3044\u308b\u3088\u3046\u3067\u3059\u3002<br \/>\n<strong>\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u306a\u3057<\/strong>\u3067\u306f\u9023\u756a\u3067\u30b9\u30ec\u30c3\u30c9ID\u304c\u8868\u793a\u3055\u308c\u3066\u304a\u308a\u3001\u6bce\u56de\u65b0\u3057\u3044\u30b9\u30ec\u30c3\u30c9\u3092\u751f\u6210\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n<pre>\n$ java ThreadPoolTest # \u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u3042\u308a\nThread:11\nThread:19\nThread:17\nThread:13\nThread:15\nThread:11\nThread:19\nThread:17\nThread:13\nThread:15\nThread:11\nThread:17\n...\nThread:19\n$ java ThreadPoolTest # \u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u306a\u3057\nThread:11\nThread:12\nThread:10\nThread:13\nThread:14\nThread:15\nThread:16\nThread:17\nThread:18\nThread:19\nThread:20\nThread:21\n...\nThread:110\n<\/pre>\n<p>\u3082\u3061\u308d\u3093\u4eca\u56de\u3082 jstack \u3067\u78ba\u8a8d\u3057\u307e\u3057\u305f\u3002\u60f3\u5b9a\u901a\u308a\u30b9\u30ec\u30c3\u30c9\u304c5\u3064\u4ee5\u4e0a\u306b\u5897\u3048\u308b\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u3067\u3057\u305f\u3002\u30b9\u30ec\u30c3\u30c9\u540d\u306e\u300c<strong>pool-1-thread-...<\/strong>\u300d\u306fExecutorService\u3092\u4f7f\u3063\u305f\u969b\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u306e\u30b9\u30ec\u30c3\u30c9\u540d\u306a\u306e\u3067\u3001\u30b9\u30ec\u30c3\u30c9\u30d7\u30fc\u30eb\u304c\u4f7f\u308f\u308c\u3066\u3044\u308b\u3053\u3068\u304c\u308f\u304b\u308a\u307e\u3059\u3002<\/p>\n<pre>\n...\n\"pool-1-thread-5\" #19 prio=5 os_prio=0 tid=0x00007ffabc0ffa10 nid=0x53cd waiting on condition [0x00007ffa7f4f3000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadPoolTest$SampleThread1.run(ThreadPoolTest.java:10)\n...\n\"pool-1-thread-4\" #17 prio=5 os_prio=0 tid=0x00007ffabc0fe5d0 nid=0x53cc waiting on condition [0x00007ffa7f5f4000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadPoolTest$SampleThread1.run(ThreadPoolTest.java:10)\n...\n\"pool-1-thread-3\" #15 prio=5 os_prio=0 tid=0x00007ffabc0fd110 nid=0x53cb waiting on condition [0x00007ffa7f6f5000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadPoolTest$SampleThread1.run(ThreadPoolTest.java:10)\n...\n\"pool-1-thread-2\" #13 prio=5 os_prio=0 tid=0x00007ffabc0fbd10 nid=0x53ca waiting on condition [0x00007ffa7f7f6000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadPoolTest$SampleThread1.run(ThreadPoolTest.java:10)\n...\n\"pool-1-thread-1\" #11 prio=5 os_prio=0 tid=0x00007ffabc0fab80 nid=0x53c9 waiting on condition [0x00007ffa7f8f7000]\n   java.lang.Thread.State: TIMED_WAITING (sleeping)\n        at java.lang.Thread.sleep(Native Method)\n        at ThreadPoolTest$SampleThread1.run(ThreadPoolTest.java:10)\n...\n<\/pre>\n<h2 id=\"fin\">\u304a\u308f\u308a\u306b<\/h2>\n<p>Java \u3067\u306e\u30d7\u30ed\u30bb\u30b9\/\u30b9\u30ec\u30c3\u30c9\u5468\u308a\u3092\u89e6\u3063\u3066\u307f\u307e\u3057\u305f\u3002\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u5b9f\u884c\u7d50\u679c\u3060\u3051\u3067\u306a\u304f\u3001\u300cps\u300d\u3084\u300cjstack\u300d\u3068\u3044\u3063\u305f\u30b3\u30de\u30f3\u30c9\u3084\u30c4\u30fc\u30eb\u3092\u4f7f\u3046\u3053\u3068\u3067\u3088\u308a\u5185\u90e8\u306e\u52d5\u304d\u3092\u30a4\u30e1\u30fc\u30b8\u3057\u3084\u3059\u304f\u306a\u308a\u307e\u3057\u305f\uff01<br \/>\njstack \u306f\u672c\u756a\u74b0\u5883\u3067\u306e\u8abf\u67fb\u306a\u3069\u3067\u4f7f\u3046\u3053\u3068\u304c\u3042\u308b\u306e\u3067\u3001\u6163\u308c\u3066\u304a\u3053\u3046\u3068\u601d\u3044\u4e00\u7dd2\u306b\u52c9\u5f37\u3057\u305f\u306e\u3067\u3064\u3044\u3067\u306b\u8f09\u305b\u307e\u3057\u305f\uff01\u30b9\u30ec\u30c3\u30c9\u306b\u3064\u3044\u3066\u306f\u52b9\u7387\u3088\u304f\u4e26\u5217\u51e6\u7406\u3059\u308b\u305f\u3081\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3084\u8a70\u307e\u308a\u30dd\u30a4\u30f3\u30c8\u3001\u4fbf\u5229\u306a\u30d5\u30ec\u30fc\u30e0\u30ef\u30fc\u30af\u304c\u305f\u304f\u3055\u3093\u3042\u308b\u3088\u3046\u306a\u306e\u3067\u3001\u5f15\u304d\u7d9a\u304d\u52c9\u5f37\u3057\u3066\u3044\u304d\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u3053\u3093\u306b\u3061\u306f\u3002\u938c\u7530\u3067\u3059\u3002<br \/>\n\u3053\u308c\u306f TECHSCORE Advent Calendar 2018\u306e13\u65e5\u76ee\u306e\u8a18\u4e8b\u3067\u3059\u3002<\/p>\n<p>Java \u3067\u306e\u30d7\u30ed\u30bb\u30b9\u3084\u30b9\u30ec\u30c3\u30c9\u306e\u5b9f\u88c5\u65b9\u6cd5\u3064\u3044\u3066\u3042\u307e\u308a\u7406\u89e3\u3067\u304d\u3066\u3044\u308b\u6c17\u304c\u305b\u305a\u3001\u3042\u3089\u305f\u3081\u3066\u52c9\u5f37\u3059\u308b\u610f\u5473\u3067\u89e6\u3063\u305f\u3053\u3068\u3092\u8a18\u4e8b\u306b\u3057\u307e\u3057\u305f\u3002<br \/><a href=\"https:\/\/www.techscore.com\/blog\/2018\/12\/13\/java-process-thread-study\/\">\u7d9a\u304d\u3092\u8aad\u3080...<\/a><\/p>\n","protected":false},"author":63,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[308,261,18],"tags":[141,57],"_links":{"self":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/19631"}],"collection":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/users\/63"}],"replies":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/comments?post=19631"}],"version-history":[{"count":95,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/19631\/revisions"}],"predecessor-version":[{"id":21246,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/19631\/revisions\/21246"}],"wp:attachment":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/media?parent=19631"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/categories?post=19631"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/tags?post=19631"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}